(a) Field of the Invention
The present invention is related to a charging device, and more particularly to a multi-purpose, portable charger to charge a first battery or at least one set of identical or different second batteries, and to execute emergency charging to the second battery by the first battery.
(b) Description of the Prior Art
A charger of the prior art usually has its power supplied from a DC output rectified from an AC source, or directly from a DC source, such as from a cigarette lighter in an automobile, to charge a battery placed in a battery holder. Alternatively, a battery already fully charged is placed into the battery holder to output through a plug and socket set for serving as an emergency charger. However, both are of standing alone types and once used up, the emergency charger is replaced with a new one, or in case of a rechargeable type, another charger is required to charge the emergency charger. Therefore, it is not economical or convenient to carry both types of chargers.
The primary purpose of the present invention is to provide a charging device that allows two-way input and output provided by a battery holder, essentially comprised of a charging source, a charging circuit, a holder of the first battery, at least one unit of second battery holder or at least one plug and socket unit to externally output charging potentials, a casing and an indicator characterized by that:
(1) an external source is used to charge a first battery in the first battery holder through the charging circuit;
(2) the external source is also used through the charging circuit, or one unit or multiple units of plug and socket to charge one unit or multiple units of second battery holder;
(3) the external source is further used through the charging circuit to charge the first battery from the first battery holder, and to charge one unit or multiple units of second battery through one unit or multiple units of the second battery holder, or through one unit or multiple units of the plug and socket set; and
(4) the battery placed in the first battery holder is used through the charging circuit to charge one unit or multiple units of the second battery holder; or to charge one unit or multiple units of the second battery through one unit or multiple units of the plug and socket set.